Sock



FIG. 1 is a front view of a sock showing my new design;

FIG. 2 is a rear view of the sock;

FIG. 3 is a left side view of the sock;

FIG. 4 is a right side view of the sock;

FIG. 5 is a top view of the sock; and,

FIG. 6 is a bottom view of the sock.

The broken lines showing lettering form no part of the claimed design. 

CLAIM The ornamental design for a sock, as shown and described. 